Author Topic: Looking for a vacuum fitting for a 1981 Quadrajet  (Read 350 times)

Offline wheelz

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Looking for a vacuum fitting for a 1981 Quadrajet
« on: July 04, 2023, 07:16:02 PM »
Anyone know where I can find a vacuum fitting located on the rear of the baseplate for a 1981 Quadrajet?

This baseplate has the large size opening...1/2" NPT I believe...according to my measurement.

Should look like this pic

Offline Kenth

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #1 on: July 05, 2023, 01:18:22 AM »
Your picture shows a Pontiac 1/8" NPT fitting used on carbs up to 1974.
1975 and later Pontiac Qjets uses 1/4" NPT fittings of the same type, but you can use an adapter.
The early fitting can be found at amesperf.com

Offline Cliff Ruggles

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #2 on: July 05, 2023, 05:52:11 AM »
What fitting are you looking for?

The later carbs used 1/4NPT threads and most had a 1/4"NPT to 3/8" inverted flare fitting for the metal line up to the power brakes. 

Some folks use 1/4NPT to 3/8" hose fittings instead.

I have PLENTY of factory 1/4NPT to inverted flare fittings in spare parts.  Plus I have several of the 1/4NPT fittings that Pontiac used on their carbs for power brakes, trans modulator, etc.

I also have a few of the earlier 1/8NPT fittings and the adapters to install them in the later carburetors....
« Last Edit: September 28, 2023, 08:25:14 PM by Cliff Ruggles »

Offline wheelz

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #3 on: July 05, 2023, 06:29:09 AM »
Found my actual broken fitting.
The photo has my broken 1981 fitting, and another from 1973, just for reference.

Offline wheelz

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #4 on: July 05, 2023, 11:52:31 AM »
Cliff,
From the photo you can see what broke, and what I need replaced.
Fortunately I was able to easily remove the broken piece from the baseplate.

This is one of your carb rebuilds that you did for me 20 years ago btw.
Always ran very well, so I am anxious to keep it in proper condition and reinstall it.




Offline Mr.Pontiac

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #5 on: September 26, 2023, 08:27:25 AM »
Contact me, I may have one, 50-50 chance

Offline wheelz

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Re: Looking for a vacuum fitting for a 1981 Quadrajet
« Reply #6 on: September 26, 2023, 08:55:59 AM »
Thanks, but I went ahead and got an adapter for the older fitting.